1 / 22

Reminders

Reminders. Case Studies: Due Wed., March 19- DUE TODAY Exam 3- Wed., March 26 Chapters 3, 5, & 6. Chapter 6- T Cell-Mediated Immunity. The 3 different APCs have different roles in the immune response. Distribution of APC in the secondary lymphoid tissue- lymph nodes:.

lanai
Download Presentation

Reminders

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Reminders • Case Studies: • Due Wed., March 19- DUE TODAY • Exam 3- Wed., March 26 • Chapters 3, 5, & 6.

  2. Chapter 6- T Cell-Mediated Immunity The 3 different APCs have different roles in the immune response.

  3. Distribution of APC in the secondary lymphoid tissue- lymph nodes: Marginal sinus where lymph collects.

  4. The Dendritic Cells

  5. The Dendritic Cells • Dendritic Cells are derived from myeloid & lymphoid progenitors in the bone marrow. • (not follicular DC) • Immature DC travel to peripheral tissues & organs: • Surface epithelial areas: gut, respiratory tract, skin • Heart & kidneys etc. • Waiting for encounters with antigen!

  6. Migration from the peripheral site of infection to the lymphoid tissue stimulates maturation. Langerhans cells

  7. Proteins Labeled: • MHC class II- green. • Lysosomal protein-red • fig 8-9, Janeway

  8. Mature Dendritic Cell in the Lymph Node: N C C • “Interdigitating Reticular Cells” C

  9. - Lectin - Induces macropinocytosis • MHC • B7 • DC-SIGN & CAMs to interact with naïve T cells. • chemokine receptors (CCRs)- CCR7 • CCL18 = chemokine Immature DC express different surface molecules as compared to the mature DC:

  10. Resting Mf can’t activate naïve T cells & poorly activate effector T cells. Why? The Macrophage • Requires activation: • Cytokines &/or binding of pathogens or their products. • Upregulates MHC class II & B7.

  11. Mf is best at internalizing particulate Ag & bacteria!

  12. Adjuvants- • a substance (often microbial in origin) that will induce production of a costimulatory response in APC- • used when making a vaccine with soluble antigen.

  13. B cells are adapted to take in soluble antigen. Expressed on MHC that is constitutively expressed. Naïve B cells generally require a Th2 response before becoming activated.

  14. B cells are less important for activating “naïve T cells”.

  15. How does the binding of TCR to MHC-Ag mediate cell signaling? Signal Transduction Pathway- Common themes in Lymphocyte activation:

  16. 1. Signal Transduction requires the crosslinking of receptors: • Successful signal requires ~100 TCR binding MHC-peptide @ a given time. • Each MHC must carry same peptide! • Coreceptor is required!

  17. Janeway • 2. TCR complex & Coreceptor must associate with “Receptor Associated Tyrosine Kinases (RATK): • ITAMs- Immunoreceptor tyrosine-based activation motifs: • AA seq in the TCR complex cytoplasmic tails that are bound by kinases. • 2 tyr residues

  18. Who are the RATKs? • Src Family- • Fyn- associates with ITAM in zz chains & e of CD3. • Require clustering of receptors to associate. • Lck- always associates with CD4 or CD8. • ZAP-70- Tyr kinase responsible for signal cascade. • SH2 domains- binds P-Tyr in ITAMs in the zz chains

More Related